Carpenter&#39;s square.



0. FORSBERG.-

CARPENTEWS SQUARE.

Y APPLICATION` FILED JUNE 26. |915. I i 1,178,710. Pat-@med Apr.11,1916.

-.. 22h85 v D* x 1, l

` F0 s BE Re @Hmm/.seo l www W 1 0, 1Q, 1W- f @www I I Y a fllto'wnmz`THB COLUMBIA PIANOGRAPM p0., WASHINGTON, D. C.

1 UNITED STATESPATENI @Erice y j escala FORSBERG, onyoivnnns, NEW YORK.

TaaZZ whom t .ou/oy concern.;

' are indicated.

Be it known thatfI, OSCAR Fonsnnma citizen of the United States,residing at Nepperhan Heights, Yonkers, in the county of Westchester andState of New York, have invented certain new and useful Improvements inCarpenters Squares, of which the following is a specification, referencebeing had to the accompanying drawings. f

This invention relates `to carpenters squares, and has for its primaryobject to provide a square, the tongue and blade of whichv are providedwith suitable scales, whereby rthe length .of roof rafters of va-'`rious kinds, may be determined.

IThe invention has for a further objectto provide a relativearrangementgof the scales upon the tongue and blade of the square@-whereby the actual determination of rafter lengths may be greatlyfacilitated and the necessity of making numerous calculations,lobviated.

With the above and other objects in view, my invention consists in thenovel .featuresl ofv construction, combination, and arran-gement ofparts to behereinafter more fully, p

described, claimed, and illustrated in the accompanying drawing,inwhich,

Figure .l is a plan view of my improvedv carpenters square havingimaginary lines" laid off thereon to show the manner whereby the lengthof they several different `kinds of roof rafters may be determined; andFig. 2 illustrates several diagrams on which rafters employed forseveraldiEerent purposes y f length of the common rafters for a roof ofReferring in detail to the drawing, 5 desy ignates the long body bladeof the square and 6 the relatively short tongue which eX- tends fromAone end of the blade at right angles thereto. The outer edge of theblade 5 is graduated to provide a scale 7 graduated in inches andtwelfths thereof to represent feet and inches. The outer edge of thetongue 6 is also provided with a scale indicated at 9, the graduationsthereof also representing feet and inches. l

A second longitudinal scale Sis provided upon the blade 5 which bearsthe same relation to either of the scales 7 or 9 that thev diagonal of asquare does to its sides, and

is adapted for use only in laying out square y j ascertain the necessarylength of a bracingH pitched roofs.

Having vabove described the several features of the combined carpenterssquare and I scale, I shall now set forth several wayspfin icARPEN'rERs' SQUARE. v f

`Specification of Letters Patent.

l' Application mea June 2e, 1915. serial No. 36,545.

"Patent-@uam 11,1916.

which the Same may be advantageously emgployed.

i Referrlng to the diagram :in Fig. 2, showf` ing the plfan of aroof`when it is desiredA to determine the lengthof the common'rafn tersindicated bythe letters .C. B vfor a roof having arise or heightof 13',1%","this measurement lof 1 3', 11?" is laid` off on the scale 8 ofthesquareblade 5 `and projected through thescale 7 which will give Vareading of 18', 6%", which will be the true length of the commonrafters. i

To determine the necessary p length lof thev valley rafters, indicatedin' the diagram rby the letters V. R., the 13', 1%" measurement n islaid olf onthe scale 9 of the tongue Gand a separate scale, indicated atB, extending from thispoint on the sca-le` 9 to the 18',

6%" graduation on thescale 7 of the square blade,will give a reading of22', 8%" which isthe truey length ofthe valleyraftersi' It is, of;course, understood f that "theseparate scale for taking thesemeasurements from 1 g the blade and tongueof the `square-:isprogerlygraduated. y

Assuming that the rise or height ofthe roofis 7', 8" insteadof 13', 1%",the run being 13', 19j", thisymeasurement is laid 'off onthe scale 7,the graduations thereon being measurement is laid .off on the-scalel 9ofthe tongue 6. .A scalelaid upon the blade andk tongue ofy the squareand connecting these'y 'l vtwo points, will give a measurement of' 15',29;" as indicated at C, whichisfhthe separate scale indicated at D willgive a measurement of 20', 1%,r whichfis the desired length of thevalleyrafters.

In order to determinethe necessary length'.`

of braces between tw'o beams ofa triangularshaped figure, the same areread'upon the 'l y 105 A l scales 7 and 8. Forinstance, assuming, as

13', 11i gradu-` ation on the scale 8 projectedthrough the scale 7 onthe edge of the square. blade, thev shown in one of the diagrams in Fig.2, .that two sides of the triangle which are known each measures 4', 8",and it is desired to beam to connect the ends of these two sides,

the measurement 4', 8" on the inner scaleS projected through the scale7,011" the outer edge yofthe blade 5, as indicated at E, which will givea reading of 6', 7%, which is the necessary length of the brace.` Again,

assuming that the length of the brace be.

given as 8, 11 and it is desired to determine thelength-of the other twosides of the triangle' which are tobe equal, the measurement 8, l1 islaid off on the scale 7 and projected throughthe scale 8 as indicated atF, which willgive a reading of 6, 3% on the latter scale, or thenecessary length for the other two pieces.

From the above description, it is believed that the manner of using myimproved scale in roof construction will be clearly and fullyunderstood. y

' 'It-is, of course, obvious that the above are onlyv given 'as examplesand the device may be employed for various other analogous uses..

The graduations for the several scales being marked directly upon theblade and tongue: on the carpenters square, it is ap@ parent that'thecalculations may be very easily and quickly made Without requiring thehandling of a number of rules.

The' .invention is also very convenient and servi'ceablein practical useand it is, of

course,l apparent that the same can be produced'at only slightly greatercost than that incident tothe manufacture of the square itself.V

v'Having thus fully described my invention, Awhat 1 desire to claim andsecure by Letters Patent is 1. A square having a blade and tongue, saidblade being provided upon its outer edge with a scale indicative ofcommon rafter lengths for various roof constructions and valso providedwith a second scale upon which the rise of the roof is adapted to belaid off, the length of the common roof rafter for a roof having a givenrise being determined by projecting the graduation on the latter scalecorresponding to such rise on to the first named scale.

2. A square having a blade and tongue, said blade being provided withtwo longitudinallv extending scales having their graduations atrelatively different distances apart and each being indicative of feetand fractional parts thereof, the rise of a roof being adapted to belaid 0H on one of said scales by the projection of the graduationcorresponding to such rise onto the other scale, the reading onsaidlatter scale indicating the necessary length of the common roof rafters.

3. A square having a blade and tongue,

`said blade being provided with two longitudinally extending scaleshaving their graduations at relatively different distances apart andeach being indicative of feet and fractional parts thereof, the run of aroof rafter being adapted to be laid off on one of said scales andprojected onto the other of the scales, the reading on said latter scaleindicating the necessary length of the common roof rafters or the run ofthe valley rafter, said tongue being also provided with a longitudinallyextending scale graduated to in- -dicate feet and fractional partsthereof and upon which the rise is adapted to be laid,

off, the distance between the graduation giving the run of the valleyrafter and that on the tongue corresponding to suchA rise giving thelength of said valley rafter.

In testimony whereof I hereunto affix my signature in the presence oftwo witnesses.

OSCAR FORSBERG.

Witnesses:

SWAN KNUTsoN, VITALIs JoHNsoN.

Copies of this' patent may be obtained for ve cents each, by addressingthe Commissioner of Patents.

Washington, D. C."

